This chapter presents an overview of bioelectronics’ underlying theory and practical

applications, focusing on fundamental concepts, materials, fabrication, and testing of

bioelectronic tools.

1.2 Fundamental Concepts of Bioelectronics

Multidisciplinary research fields including electrical engineering, biology, chemical, and

physical science, and material science are required to fully realize the promise of bioe­

lectronics. Even though the field of bioelectronic medicine is still in its infancy, the op­

portunities and hopes it inspires are vast. A revolution in medical practice, not an

innovation, is what bioelectronic medicine is all about. New bioelectronics disciplines

have the potential to have an enormous influence on a wide range of national priorities,

including healthcare and medicine, homeland security, forensics, and environmental and

food supply protection. The synergy between electronics and biology might be greatly

enhanced with the evolution of electronic technology to the atomic scale, as well as major

advances in system, cell, and molecular biology. A lab-on-a-chip for a clinic for medical

diagnosis, and real-time detection of biological agents would eliminate the need for a

laboratory in the next decades. This section will introduce the reader to the principles of

working with bio-interfaces, which are junctions between different materials and biolo­

gical structures. The discussion of the size and time of interactions, material selection, and

the basic biophysical ideas is highlighted to explain how biological events happen and

how their signals can be interpreted in terms of bioelectronics.

1.2.1 Bioelectronics with a Size Scale

When designing the bio-interfaces, it is important to consider the length scale of the

interface to effectively address the relevant biological events. These can range from

the large area with non-specific modulation to micro-sensing and everything in between

(Figure 1.2a). Electrodes with a large surface area were the first such device developed

and still in use. There are many more frequently used advanced techniques available like

electroencephalography (EEG) to record brain activity through the scalp, electro­

cardiography (ECG) to monitor cardiac activity, and electromyography (EMG) to record

skeletal muscle activity [2].

The advances in materials research have opened the door to the possibility of con­

structing probes with higher resolution that can be placed closer to the active cells, en­

abling the creation of smaller and less invasive devices to be built. The first phase was the

development of direct bio-interfaces with a single organ, which was completed in two

stages. The second step was the establishment of indirect bio-interfaces with a single

organ. Because of these efforts, artificial pacemakers, cochlear implants, and deep-brain

stimulation probes have all been produced, and they have helped millions of people live

longer, better lives. Probes have shortened in size and grown more adaptable, which has

resulted in an improvement in the biocompatibility of electrical devices [3–5]. They

opened up an entirely new viewpoint on the study of cell physiology since micron-sized

devices were able to detect local electric potential deep within tissues while also inter­

acting with small groups of cells, making them an invaluable tool in the field. To operate

at this scale, it is required to consider major chemical interactions between the materials

Introduction to Bioelectronics

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